Mutant/mutation
The mutant lacks expression of perforin like protein 2  (PPLP2).

Protein (function)
The pplp2 gene is a member of a small, conserved family of proteins encoding perforin-like proteins containing membrane-attack complex/perforin domains (MACPF)(Kaiser, K et al., 2004, Mol. Biochem. Parasitol. 133, 15-26).

Phenotype
The mutant produces normal numbers of gametocytes. However, the production of male gametes is affected. The male gametocyte displays abnormal exflagellation; instead of forming 8 gametes, it produced only one, shared thicker flagellum. Evidence is presented that rupture of the erythrocyte membrane is blocked and thereby preventing egress of male gametes from the erythrocyte. Evidence is presented that the parasitophorous vacuole membrane is ruptured normally in activated mutant male gametocytes.
Evidence is presented that female gametocytes/female gametes show normal egress from the erythrocyte (see below).

The mutant produces low numbers of ookinetes, oocysts and sporozoites. Sporozoites are infectious to mice. These results indicate that PPLP2 has a specific role in egress of male gametocytes/gametes from the erythrocyte.

Additional information
Pplp2 mRNA was exclusively detected in gametocytes and ookinetes (by RT-PCR). The protein was only  detected in gametocytes and not in ookinetes which may indicate that  the signal detected in the RT-PCR analysis may originate from gametocytes remaining in the ookinete preparation. Expression of PPLP2 could not be detected in asexual parasites of parasites which are deficient in the production of gametocytes.
The PPLP2 protein was only detected in P. berghei male and not in P. berghei female gametocytes (in P. falciparum PPLP2 was detected in both male and female gametocytes). The PPLP2 protein could not be detected in activated male gametocytes rapidly after activation of male gametocytes,

Crossing of pplp2(-) mutant females with wild type male gametes resulted in normal ookinete formation in vitro. This result indicates that female gametocytes/female gametes show normal egress from the erythrocyte and that the female gametes are fertile.

Other mutants